Why Are There 5,280 Feet in a Mile?

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Why are there 5,280 feet in a mile, and why are nautical miles different from the statute miles we use on land? Why do we buy milk and gasoline by the gallon? Where does the abbreviation "lb" come from? Let's take a look at the origins of a few units of measure we use every day.

The Mile

The basic concept of the mile originated in Roman times. The Romans used a unit of distance called the mille passum, which literally translated into "a thousand paces." Since each pace was considered to be five Roman feet—which were a bit shorter than our modern feet—the mile ended up being 5,000 Roman feet, or roughly 4,850 of our modern feet.

If the mile originated with 5,000 Roman feet, how did we end up with a mile that is 5,280 feet? Blame the furlong. The furlong wasn't always just an arcane unit of measure that horseracing fans gabbed about; it once had significance as the length of the furrow a team of oxen could plow in a day. In 1592, Parliament set about determining the length of the mile and decided that each one should be made up of eight furlongs. Since a furlong was 660 feet, we ended up with a 5,280-foot mile.

The Nautical Mile

So if the statute mile is the result of Roman influences and plowing oxen, where did the nautical mile get its start? Strap on your high school geometry helmet for this one. Each nautical mile originally referred to one minute of arc along a meridian around the Earth. Think of a meridian around the Earth as being made up of 360 degrees, and each of those degrees consists of 60 minutes of arc. Each of these minutes of arc is then 1/21,600th of the distance around the earth. Thus, a nautical mile is 6,076 feet.

The Acre

Like the mile, the acre owes its existence to the concept of the furlong. Remember that a furlong was considered to be the length of a furrow a team of oxen could plow in one day without resting. An acre—which gets its name from an Old English word meaning "open field"—was originally the amount of land that a single farmer with a single ox could plow in one day. Over time, the old Saxon inhabitants of England established that this area was equivalent to a long, thin strip of land one furlong in length and one chain—an old unit of length equivalent to 66 feet—wide. That's how we ended up with an acre that's equivalent to 43,560 square feet.

The Foot

As the name implies, scholars think that the foot was actually based on the length of the human foot. The Romans had a unit of measure called a pes that was made up of twelve smaller units called unciae. The Roman pes was a smidge shorter than our foot—it came in at around 11.6 inches—and similar Old English units based on the length of people's feet were also a bit shorter than our 12-inch foot. The 12-inch foot didn't become a common unit of measurement until the reign of Henry I of England during the early 12th century, which has led some scholars to believe it was standardized to correspond to the 12-inch foot of the king.

The Gallon

The gallon we use for our liquids comes from the Roman word galeta, which meant "a pailful." There have been a number of very different gallon units over the years, but the gallon we use in the United States is probably based on what was once known as the "wine gallon" or Queen Anne's gallon, which was named for the reigning monarch when it was standardized in 1707. The wine gallon corresponded to a vessel that was designed to hold exactly eight troy pounds of wine.

The Pound

Like several other units, the pound has Roman roots. It's descended from a roman unit called the libra. That explains the "lb" abbreviation for the pound, and the word "pound" itself comes from the Latin pondo, for "weight." The avoirdupois pounds we use today have been around since the early 14th century, when English merchants invented the measurement in order to sell goods by weight rather than volume. They based their new unit of measure as being equivalent to 7000 grains, an existing unit, and then divided each 7000-grain avoirdupois pound into 16 ounces.

Horsepower

Early 18th-century steam engine entrepreneurs needed a way to express how powerful their machines were, and the industrious James Watt hit on a funny idea for comparing engines to horses. Watt studied horses and found that the average harnessed equine worker could lift 550 pounds at a clip of roughly one foot per second, which equated to 33,000 foot-pounds of work per minute.

Not all scholars believe that Watt arrived at his measurement so scientifically, though. One common story claims that Watt actually did his early tests with ponies, not horses. He found that ponies could do 22,000 foot-pounds of work per minute and figured that horses were half again stronger than ponies, so he got the ballpark figure of 33,000 foot-pounds of work per minute.

Why Do Supreme Court Justices Serve for Life?

Alex Wong, Getty Images
Alex Wong, Getty Images

There are few political appointments quite as important as a nomination to the U.S. Supreme Court. Unlike a cabinet secretary or an ambassador, justices serve for life. In the modern era, that often means more than three decades on the court—thanks to increased lifespans, justices appointed in the next century are expected to sit on the Supreme Court for an average of 35 years, compared to the average of around 16 years that judges served in the past. Because of this shift, some scholars have begun to question whether lifetime appointments are still appropriate, as the definition of “for life” has changed so much since the constitution was written. But why do justices serve for life, anyway?

Well, for one thing, the U.S. Constitution doesn’t exactly specify that justices and the court are in a “’til death do us part” relationship. Article III says that judges (of both the Supreme Court and lower federal courts) “shall hold their offices during good behavior.” So technically, a judge could be removed if they no longer meet the “good behavior” part of the clause, but there are otherwise no limits on their term. In practice, this means they have their seat for life, unless they are impeached and removed by Congress. Only 15 federal judges in U.S. history have ever been impeached by Congress—all lower court judges—and only eight have been removed from office, though some have resigned before their inevitable removal.

The only Supreme Court justice Congress has tried to impeach was Samuel Chase, who was appointed by George Washington in 1796. Chase was an openly partisan Federalist vehemently opposed to Thomas Jefferson’s Democratic-Republican policies, and he wasn’t afraid to say so, either in his role as a lower court judge or once he was appointed to the Supreme Court. In 1804, the House of Representatives, at then-president Jefferson’s urging, voted to impeach Chase, accusing him, among other things, of promoting his political views from the bench instead of ruling as a non-partisan judge. However, he was acquitted of all counts in the Senate, and went on to serve as a Supreme Court justice until his death in 1811.

The point of giving justices a seat on the bench for the rest of their lives (or, more commonly nowadays, until they decide to retire) is to shield the nation’s highest court from the kind of partisan fighting the Chase impeachment exemplified. The Supreme Court acts as a check against the power of Congress and the president. The lifetime appointment is designed to ensure that the justices are insulated from political pressure and that the court can serve as a truly independent branch of government.

Justices can’t be fired if they make unpopular decisions, in theory allowing them to focus on the law rather than politics. Justices might be nominated because a president sees them as a political or ideological ally, but once they’re on the bench, they can’t be recalled, even if their ideology shifts. Some data, for instance, suggests that many justices actually drift leftward as they age, no doubt infuriating the conservative presidents that appointed them.

The lack of term limits “is the best expedient which can be devised in any government, to secure a steady, upright and impartial administration of the laws,” Alexander Hamilton wrote in the Federalist No. 78. The judiciary, he believed, “is in continual jeopardy of being overpowered, awed, or influenced by its coordinate branches,” and “nothing can contribute so much to its firmness and independence, as permanency in office.” Without lifetime job security, he argued, judges might feel obligated to bow to the wishes of the president, Congress, or the public, rather than confining their work strictly to questions of the Constitution.

While lifetime appointments may be a longstanding tradition in the U.S., this approach isn’t the norm in other countries. Most other democracies in the world have mandatory retirement ages if not hard-and-fast term limits for high court judges. UK Supreme Court justices face mandatory retirement at age 70 (or 75 if they were appointed before 1995), as do judges on Australia’s High Court. Canadian Supreme Court justices have a mandatory retirement age of 75, while the 31 justices of India’s Supreme Court must retire by the age of 65. Meanwhile, the oldest justice now on the U.S. Supreme Court, Ruth Bader Ginsburg, is currently 85 and kicking. Oliver Wendell Holmes Jr., the oldest justice in U.S. history, retired in 1932 at age 90.

Though the U.S. Supreme Court has never had term limits before, there have recently been serious proposals to implement them. Term limits, advocates argue, could combat partisan imbalances on the court. Presidents wouldn’t get to appoint justices purely based on whether someone died while they were in office, and the stakes for political parties nominating a justice would be slightly lower, possibly leading presidents and Congress to compromise more on appointments. One popular suggestion among political analysts and scholars is to impose an 18-year term limit, though critics note that that particular plan does bring up the potential that at some point, a single president could end up appointing the majority of the justices on the court.

In any case, considering such a change would likely require a constitutional amendment, which means it’s probably not going to happen anytime soon. For the foreseeable future, being on the Supreme Court will continue to be a lifetime commitment.

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How Often Should You Poop?

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When it comes to No. 2, plenty of people aren’t really sure what’s normal. Are you supposed to go every day? What if you go 10 times a day? Is that a sign that you’re dying? What about once every three days? Short of asking everyone you know for their personal poop statistics, how do you know how often you’re supposed to hit the head?

Everyone’s system is a little different, and according to experts, regularity is more important than how often you do the deed. Though some lucky people might think of having a bowel movement as an integral part of their morning routine, most people don’t poop every day, as Lifehacker informs us. In fact, if you go anywhere between three times a day and three times a week, you’re within the normal range.

It’s when things change that you need to pay attention. If you typically go twice a day and you suddenly find yourself becoming a once-every-three-days person, something is wrong. The same thing goes if you normally go once every few days but suddenly start running to the toilet every day.

There are a number of factors that can influence how often you go, including your travel schedule, your medications, your exercise routine, your coffee habit, your stress levels, your hangover, and, of course, your diet. (You should be eating at least 25 to 30 grams of fiber a day, a goal that most Americans fall significantly short of.)

If you do experience a sudden change in how often you take a seat on the porcelain throne, you should probably see a doctor. It could be something serious, like celiac disease, cancer, or inflammatory bowel disease. Or perhaps you just need to eat a lot more kale. Only a doctor can tell you.

However, if you do have trouble going, please, don’t spend your whole day sitting on the toilet. It’s terrible for your butt. You shouldn’t spend more than 10 to 15 minutes on the toilet, as one expert told Men’s Health, or you’ll probably give yourself hemorrhoids.

But if you have a steady routine of pooping three times a day, by all means, keep doing what you’re doing. Just maybe get yourself a bidet.

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